Unmanned aerial vehicles, UAVs for short, are unmanned aircrafts controlled by radio remote equipment and self-contained program control devices. With advantages of small size, light weight, low costs, flexible operation, and high safety, UAVs are widely used for such fields as aerial photography, detection, search and rescue, resource exploration, and the like. However, during flying, UAVs are subjected to big shake and strong vibration. To ensure the quality of the aerial photo graph and protect the aerial equipment, a pan-tilt unit is employed to coordinate with the aerial equipment to improve the flight stability. Conventional pan-tilt units are complex in structure, large in size, and the shock absorber ball tends to loosen and fall off, causing the detachment of the pan-tilt units, which poses a hidden danger.